硫源种类对微波合成CZTS颗粒与薄膜性能的影响

研究不同硫源对微波液相合成的Cu２ＺｎＳｎＳ４（CZTS）纳米颗粒尺寸及形貌的影响。结果表明：当采用硫脲作为硫源时，所制备的CZTS纳米颗粒为平均尺寸500 nm的球状结构纳米颗粒;采用L 半胱氨酸作为硫源所制备的CZTS纳米颗粒为50 nm的空心球状纳米颗粒；而当使用硫代乙酰胺作为硫源制备CZTS纳米颗粒，其平均尺寸仅为3 nm。采用 平均尺寸为500 nm或50 nm的纳米颗粒制备墨水，将墨水旋涂到衬底上时，其致密性很差，明显存在许多孔洞。当采用平均尺寸为3 nm的纳米颗粒制作墨水，并将其制成薄膜时，薄膜致密性与均匀性都比较好。将最佳的预制薄膜进行硫化处理，其结晶性明显提高，并得到转化效率为2.1%的CZTS太阳电池。

Effect of Sulfur Source on Properties of CZTS Particles by Microwave Irradiation Assisted Solvothermal Method and Thin Films

The influence of different sulfur sources on the size and morphology of Cu2ZnSnS4(CZTS) nanoparticles is studied by the microwave irradiation assisted solvothermal method. The results show that:500 nm sphere-like CZTS nanoparticles are synthesized with thiourea as a sulfur source. The 50 nm hollow sphere-like CZTS nanoparticles are obtained using L-cysteine as a sulfur source. And the average size of CZTS nanoparticles with thioacetamide as a sulfur source is only 3 nm. The nano-ink is firstly prepared by large size nanoparticles (average size of 500 nm or 50 nm). When this nano-ink is used to prepare thin film by spin-coating, the as-obtained thin film has poor density and many holes. However, when the nano-ink prepared by small size nanoparticles (average size of 3 nm) is used to prepare thin film, the thin film with best density and uniformity is obtained. Moreover,when the best as-prepared thin film is sulfurized,its crystallinity is obviously improved, and the CZTS solar cell with 2.1% efficiency is obtained.